The invention relates to protective apparel and particularly a protective suit which protects the user/wearer against the adverse effects of chemical, biological, nuclear and like environmental contamination.
Typical of such protective garments designed to protect workers in hazardous or contaminated environmental areas is exemplified by the protective garment disclosed in U.S. Pat. No. 4,272,851 in the name of Lynn E. Goldstein issued June 16, 1981. While fundamentally sound in theory, this protective garment includes numerous disadvantages, most notable of which is the utilization of an external pressurized source for introducing pressurized clean filtered breathable air into the garment. This pressurization creates an automatic "tether" which limits mobility of the wearer and the "balloon" effect of the pressurization creates added restrictions to mobility and dexterity, not to mention the fact that internal fresh air and exhaled air creates condensation which undesirably accumulates upon the associated transparent visor of the hood. Thus, while the protective garment is, as noted earlier, fundamentally sound in certain specifics (ultrasonic welding of seams), it is structurally and functionally unsound in areas of utmost concern, namely, maximum protection, filtration, mobility, comfort, durability and internal condensation-resistance.
Other protective garments not only isolate the wearer from hostile environments, but attempt to do so through a "closed circuit" type garment in which filters, valves, respirators, separate air supplies, etc. are utilized, although in some of these auxilliary external air supplies are also mentioned, as in U.S. Pat. No. 4,458,680 in the name of Edward L. Childers et al issued July 10, 1984. However, for the most part, such systems are self contained and typical so-called air supply hoods, protective gear, biological isolation garments, smoke protective hoods and/or air survival units are disclosed in representative U.S. Pat. Nos. 4,466,432; 3,185,149; 3,516,404; 4,411,023 and 4,614,186.
The utilization of mouthpieces and/or face masks in the general environment of masks, though not necessarily protective garments, is also evidenced by the patents to Warncke U.S. Pat. No. 3,680,555, Manson U.S. Pat. No. 2,062,325 and Lemere U.S. Pat. No. 4,207,882. The latter patent includes a typical scuba diving equipment mouthpiece through which air is inhaled from the exterior through filters associated with a welding mask. Exhalation through a separate branch from the mouthpiece is also provided and obviously presents the undesired high risk of environmental contamination because inhalation and exhalation are part of the same breathing system.
Surgical masks, head masks and the like, formed of relatively light-weight and disposable material are also commonplace, as evidenced by the patents to Lund et al U.S. Pat. No. 3,789,839; Saffo U.S. Pat. No. 4,583,535; and Mason Jr. et al U.S. Pat. No. 4,296,746.
Collectively these patents represent an overall background to which the present invention constitutes an unobvious and novel improvement.